Two-part endoscope surgical device

ABSTRACT

The present invention provides a two-part robotic device for positioning of a hand tool, comprising:
         a. a fixed base unit constantly fix to its position;   b. a detachable body unit reversibly coupled to said fixed base unit, coupled to said current medical instrument;
 
wherein said fixed base unit is adapted to provide independent movement to said hand tool, said independent movement selected from the group consisting of rotation and translation, and further wherein said detachable body unit is removable and replaceable from said fixed base unit such that upon exchange of said hand tool for a second hand tool, said second hand tool is placed in substantially the same location as the location of said hand tool prior to said exchange.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/086,194, filed Mar. 31, 2016, now U.S. patent Ser. No. 10/426,321,issued Oct. 1, 2019, which is a divisional of U.S. application Ser. No.13/265,206, filed Oct. 19, 2011, which is a U.S. National Stage entry ofInternational PCT Application No. PCT/IL2010/000330, filed Apr. 22,2010, which claims priority from Provisional Application No. 61/324,324,filed Apr. 15, 2010, and from Provisional Application No. 61/171,848,filed Apr. 23, 2009. All of these applications are hereby incorporatedby reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to a method and apparatus for laparoscopicsurgery using a two-part device composed of a base unit and a detachablebody unit. The invention furthermore relates to the guiding of suchlaparoscopic instruments and procedures, and in particular to interfacesthat allow identification of the spatial position of a laparoscopeduring endoscopic surgery.

BACKGROUND OF THE INVENTION

In laparoscopic surgery, the surgeon performs the operation through oneor more small incisions using long instruments, while observing theinternal anatomy with an endoscope camera. The laparoscope is oftenprovided with some form of gantry or holding unit to hold the externalportion of the device in place. This gantry is often a somewhatcumbersome apparatus and is in general associated with a particularlaparoscopic device. Each form of surgical laparoscope will have its owngantry which must be installed before use.

For example U.S. Pat. No. 5,878,193 provides a robotic system that movesa surgical instrument in response to the actuation of a control panelthat can be operated by the surgeon. The robotic system has an endeffector that is adapted to hold a surgical instrument such as anendoscope. The end effector is coupled to a robotic arm assembly whichcan move the endoscope relative to the patient. The system includes acomputer which controls the movement of the robotic arm in response toinput signals received from the control panel. The robotic system ismounted to a cart which can be wheeled to and from an operating table.

An example of laparoscopic surgery is Functional Endoscopic SinusSurgery (FESS) used to relieve blockages and discomfort in the nasalsinuses—a commonly performed operation.

During laparoscopic surgery it is often required to shift the spatialplacement of the endoscope in order to present the surgeon with anoptimal view. Conventional laparoscopic surgery makes use either ofhuman assistants who manually shift the instrumentation or alternativelyof robotic automated assistants. Automated assistants utilize interfacesthat enable the surgeon to direct the mechanical movement of theassistant, achieving a shift in the camera view. U.S. Pat. No. 6,714,841discloses an automated camera endoscope in which the surgeon is fittedwith a head mounted light source that transmits his head movements to asensor, forming an interface that converts said movements to directionsfor the mechanical movement of the automated assistant. Alternativeautomated assistants incorporate a voice operated interface, adirectional key interface, or other navigational interfaces. The maindisadvantage of the above interfaces is that they are based oncumbersome operations for starting and stopping movement directions thatrequires the surgeon's constant attention.

Arshak's article “A Model for Estimating the Real Time Positions of aMoving Object in Wireless Telemetry Applications Using RF Sensors”(Arshak, K.; Adepoju, F. Sensors Applications Symp. 2007, 1-6) relatesto a method for locating a transmitting object using multiple receivingantenna sensors located at various place surrounding the transmittingdevice. The receiver antennas are assumed to be omni-directional and thelocation of the transmitter is achieved through distance estimation(i.e., triangulation) from each of the receiving antennae.

The distance from the transmitter is estimated by measuring the receivedsignal strength (RSS) of the received signal, where the estimated RSS(in dB) is given by the following equation:

RSS=PT−PL(do)−1011 log io(d/do)+X,

where PT is the transmitted power, PL(do) is the path loss for areference distance do, ri is the pass loss exponent, d is the distancebetween the transmitter and the receiver, and X, is a Gaussian randomvariable.

Therefore, the signal received is proportional to PT and the n^(th)power of distance to the transmitter. In free space, ri is normallyequal to 2. The location of the transmitter can thus be determined byusing the above equation to calculate the distance to each of thereceiving antennas and triangulating. Arshak states in the article thatother methods such as time of arrival, time differences of arrival andangle of arrival are not feasible in dense, multipath environments. If,however, the transmission power is unknown, unstable or inaccurate, orif the propagation factor is unknown, then Arshak's method cannot beused. An efficient method for enabling the relative position of thetransmitter (and thus the medical instrument) to be determined thereforeremains a long-felt need.

Research has suggested that these systems divert the surgeon's focusfrom the major task at hand. Therefore technologies based on variouskinds of positioning systems have been developed to simplify interfacingcontrol. These technologies still fail to address another complicatinginterface aspect of laparoscopic surgery, however, as they do not allowthe surgeon to signal both to the automated assistant and to surgicalcolleagues on which surgical instrument his attention is focused.

Hence, a system for laparoscopic surgery providing multiple laparoscopictools while employing a single external holding device is a long feltneed, especially in the field of sinus surgery. Additionally there is afurther long-felt need for a device that would allow the surgeon toidentify to the laparoscopic computing system as well as to surgicalcolleagues to which surgical instrument attention is to be directed,thereby directing the view provided by the endoscope to the selectedarea of interest.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to understand the invention and to see how it may beimplemented in practice, a plurality of embodiments will now bedescribed, by way of non-limiting example only, with reference to theaccompanying drawings, in which

FIGS. 1A-D presents a Universal Joint, also known as the U-joint orCardan joint;

FIGS. 2A-B presents a constant-velocity or CV joint;

FIG. 3 presents a Thompson joint, this being a type of double Cardanjoint;

FIG. 4 presents a isometric view of an embodiment of the variablecoupling of the present invention;

FIG. 5 presents a plan view of an embodiment of the variable coupling ofthe present invention;

FIG. 6 presents an isometric view of a second embodiment of the variablecoupling of the present invention;

FIG. 7 presents a view of an embodiment of the variable coupling of thepresent invention;

FIG. 8 presents an embodiment of the variable coupling of the presentinvention where both input and output shafts have been removed;

FIGS. 9A-B presents isometric views of an embodiment of the coupling ofthe instant invention;

FIG. 10 presents an exploded view of the coupling of the currentinvention;

FIGS. 11A-B presents a gear lock release for the coupling of the currentinvention;

FIGS. 12A-D presents views of an embodiment of a shaft lock;

FIG. 13 presents three of the variable couplings of the presentinvention in series;

FIGS. 14A-B present laparoscopic positioning systems of the prior art;

FIGS. 15A-B presents a laparoscopic instrument based on the coupling ofthe current invention;

FIGS. 16A-B presents a laparoscopic instrument based on the coupling ofthe current invention;

FIGS. 17A-B and 18A-B present a laparoscopic instrument based on thecoupling of the current invention;

FIG. 19 shows a preferred embodiment of the present invention whichincorporates the positioning elements of FIGS. 15A-18B;

FIG. 20 illustrates a second embodiment of the present invention inwhich two consecutive tubular members are employed;

FIG. 21 shows a cross section of the tubular sections shown in FIG. 20;

FIGS. 22A-C illustrates an embodiment of the device in use;

FIGS. 23A-C illustrates various possible motions of the device;

FIGS. 24A-B illustrates various possibilities for operation of thedevice;

FIGS. 25A-B illustrates a general schematic views, with FIG. 25Aschematically illustrating a surgical tool positioning system thatdetects the location of a surgical tool at the time the surgeonactivates the surgical tool transmitter (manual mode) and FIG. 25Bschematically illustrating a surgical tool positioning system thatdetects the location of surgical tools continuously (continuousautomatic mode);

FIGS. 26A-C schematically illustrates methods of operation, with FIG.26A schematically illustrating sequential transmit operation, FIG. 26Bschematically illustrating periodic transmit operation, with unequalrates for left and right transmitters and FIG. 26C schematicallyillustrating simultaneous transmit operation with different frequencies;

FIGS. 27A-B schematically illustrates a view of the antenna pattern;

FIGS. 28A-D shows block diagrams, with FIG. 28A being a block diagram ofthe location system, FIG. 28B being a block diagram of an antenna set,FIG. 28C being a block diagram of the internal receiver and FIG. 28Dbeing a block diagram of the controller/sequencer;

FIG. 29 shows system control software operation flow;

FIGS. 30A-B shows the antenna switching pattern, with FIG. 30Aschematically illustrating the antenna switching pattern during periodictransmit operation and FIG. 30B schematically illustrating the antennaswitching pattern during sequential transmit operation;

FIGS. 31A-C shows examples of planar and spatial antenna structures;

FIGS. 32A-B shows examples of the use of the location system, with FIG.32A schematically illustrating use of the location system in abdominallaparoscopic surgery and FIG. 32B schematically illustrating use of thelocation system in knee endoscopic surgery;

FIGS. 33A-C shows aspects of the invention particularly suited for sinussurgery;

FIGS. 34A-B illustrates an embodiment of a system using the coupling ofthe instant invention;

FIGS. 35A-D illustrates modeling of the motion of a surgical deviceattached to the invention as the motion of a bead rotating in space;

FIGS. 36A-B illustrates means for rotating an end effector in a planeabout the long axis of the output shaft (DOF₁);

FIGS. 37A-E illustrates means for effecting motion about degree offreedom DOF₂ and the bearing that allows motion about degree of freedomDOF₃ independent of motion about degree of freedom DOF₂;

FIGS. 38A-E illustrates the relationships between means for effectingmotion about degree of freedom DOF₂ and means for effecting motion aboutdegree of freedom DOF₃;

FIGS. 39A-B illustrates means for effecting motion about degrees offreedom DOF₃-DOF₆;

FIG. 40 presents an illustration of the drive means for effecting motionabout degree of freedom DOF₄;

FIGS. 41A-E presents an illustration of the drive means for effectingmotion about degrees of freedom DOF₅ and DOF₆;

FIG. 42 presents a detailed illustration of means for effectingtranslational motion about degree of freedom DOF₅; and

FIGS. 43A-B presents a detailed illustration of means for effectingtranslational motion about degree of freedom DOF₆.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a laparoscope composed of aset of detachable parts. A base unit attaches to a fixed location suchas the floor, the side of an operating table, or the like. A body unitattaches to this base unit and is provided with a laparoscope andassociated devices, such as surgical tools, camera, fiber optics, lightsources, and the like. The body unit attaches easily to the base unitand is supported by it during surgery. It may be detached and replacedwith another body unit suitable for different procedures. The deviceutilizes a novel torque-transmitting joint that allows a large number ofdegrees of freedom to be transmitted while allowing the several sectionsof the device to be rotated and translated through additional degrees offreedom. In this way a simple and modular means for performing a widevariety of surgical procedures is attained.

It is thus an object of the present invention to disclose a two-partrobotic device for positioning of a hand tool, comprising (a) a fixedbase unit constantly fix to its position; and (b) a detachable body unitreversibly coupled to said fixed base unit, coupled to said currentmedical instrument.

It is within the essence of the invention wherein said fixed base unitis adapted to provide independent movement to said hand tool, saidindependent movement selected from the group consisting of rotation andtranslation, and further wherein said detachable body unit is removableand replaceable from said fixed base unit such that upon exchange ofsaid hand tool for a second hand tool, said second hand tool is placedin substantially the same location as the location of said hand toolprior to said exchange.

It is a further object of the present invention to disclose such atwo-part robotic device, wherein said hand tool is a medical instrument.

It is another object of the present invention to provide the two-partrobotic device as defined above, wherein said medical instrument isselected from a group consisting of endoscope, laparoscope, forceps, orany combination thereof.

It is another object of the present invention to provide the two-partrobotic device as defined above, wherein said detachable unit is anendoscope positioning device adapted to provide said endoscope at least7 DOF selected from a group consisting of at least 6 rotation movements(1007, 1009, 1010, 1011, 1012, 1013, 1601, 1602), at least 1 translationmovement (1008) or any combination thereof.

It is another object of the present invention to provide the two-partrobotic device as defined above, wherein said detachable unit comprises:

-   -   a. k consecutive arm sections, each comprising n coaxial input        shafts adapted to be rotated around an input axis of rotation by        m sources of torque, where n and m and k are positive integers;        said current instrument is coupled to one of said k consecutive        arm sections;    -   b. at least k−1 constant velocity couplers coupling each two of        said k consecutive arm sections together, each of said constant        velocity coupler comprising:        -   i. n coaxial input transmission means, each of which is            coupled to one of said n input shafts; said input            transmission means defining a first plane substantially            perpendicular to said input axis of rotation;        -   ii. n coaxial second transmission means rotatably connected            to said n input transmission means; said second transmission            means rotating in a second plane, such that said second            plane is substantially perpendicular to said first plane;        -   iii. n coaxial output transmission means rotatably connected            to said n second transmission means; said output            transmission means rotating in a third plane; said third            plane being substantially perpendicular to said second            plane;    -   c. n coaxial output shafts, each of which is coupled to one of        said n output transmission means, said n output shafts being        adapted to rotate around an output axis of rotation; such        that (i) turning a given input shaft at a constant velocity will        provide a constant velocity at the corresponding output shaft;        and, (ii) the angle between said input axis of rotation and said        output axis of rotation varies in said second plane in an        angular range of about 0 to about 360 degrees.

It is another object of the present invention to provide the two-partrobotic device as defined above, wherein said fixed base unit comprises:

-   -   a. k consecutive arm sections, each comprising n coaxial input        shafts adapted to be rotated around an input axis of rotation by        m sources of torque, where n and m and k are positive integers;        said current instrument is coupled to one of said k consecutive        arm sections;    -   b. at least k−1 constant velocity couplers coupling each two of        said k consecutive arm sections together, each of said constant        velocity coupler comprising:        -   i. n coaxial input transmission means, each of which is            coupled to one of said n input shafts; said input            transmission means defining a first plane substantially            perpendicular to said input axis of rotation;        -   ii. n coaxial second transmission means rotatably connected            to said n input transmission means; said second transmission            means rotating in a second plane, such that said second            plane is substantially perpendicular to said first plane;        -   iii. n coaxial output transmission means rotatably connected            to said n second transmission means; said output            transmission means rotating in a third plane; said third            plane being substantially perpendicular to said second            plane;    -   c. n coaxial output shafts, each of which is coupled to one of        said n output transmission means, said n output shafts being        adapted to rotate around an output axis of rotation; such        that (i) turning a given input shaft at a constant velocity will        provide a constant velocity at the corresponding output shaft;        and, (ii) the angle between said input axis of rotation and said        output axis of rotation varies in said second plane in an        angular range of about 0 to about 360 degrees.

It is another object of the present invention to provide the two-partrobotic device as defined above, wherein said input transmission means,second transmission means, and said output transmission means areselected from a group consisting of gearwheels, wheels, crown gears,bevel gears, spur gears, belts, or any combination thereof.

It is another object of the present invention to provide the two-partrobotic device as defined above, additionally comprising

-   -   a. an axial support member (601) adapted to provide axial        support to said n output shafts in said third plane; and,    -   b. a circular track (618) centered on the axis of rotation of        said second transmission means, said axial support member being        adapted to fit into said track and slide within it.

It is another object of the present invention to provide the two-partrobotic device as defined above, additionally comprising a radialsupport member (604) adapted to provide radial support to said n outputshafts, said radial support member being adapted to rotate in saidsecond plane.

It is another object of the present invention to provide the two-partrobotic device as defined above, wherein the gear ratio between saidinput and output shafts is between about 10 and about 0.1.

It is another object of the present invention to provide the two-partrobotic device as defined above, additionally comprising n coaxialauxiliary shafts in rotating communication with said n secondtransmission means, said n coaxial auxiliary shafts rotating in saidsecond plane, and said n coaxial auxiliary shafts capable of eitherbeing driven by said input shafts or driving said input shafts.

It is another object of the present invention to provide the two-partrobotic device as defined above, additionally comprising locking meansadapted for preventing relative movement between one or more of saidinput axis shafts and said constant velocity joint, wherein saidconstant velocity joint is caused to rotate as a body with said lockedinput axis shafts.

It is another object of the present invention to provide the two-partrobotic device as defined above, additionally comprising locking meansfor preventing relative movement between one or more of said output axisshafts and said constant velocity joint, wherein said constant velocityjoint is caused to rotate as a body with said locked output axis shafts.

It is another object of the present invention to provide the two-partrobotic device as defined above, adapted for use in sinus surgery.

It is another object of the present invention to provide the two-partrobotic device as defined above, wherein said sinus surgery is FESS.

It is another object of the present invention to provide a method foraltering a current medical instrument in use whilst performing alaparoscopic surgery. The method comprises steps of:

-   -   a. providing a two-part robotic device comprising:        -   i. a fixed base unit, constantly fix to its position;        -   ii. a detachable body unit reversibly coupled to said fixed            base unit, comprising said current medical instrument;

b. coupling said detachable body unit to said fixed base;

c. providing independent movements to said current medical instrumentselected from a group consisting of rotation and translation; therebyperforming said laparoscopic surgery;

d. detaching said detachable body unit from said fixed base unit; and,

e. replacing said current medical instrument in said detachable bodyunit thereby altering said current medical instrument.

It is a further object of the present invention to provide a method ofaltering the modality of a laparoscopic surgery. The method comprisessteps of:

-   -   a. providing a two-part robotic device comprising:        -   iii. a fixed base unit, constantly fix to its position;        -   iv. a first detachable body unit reversibly coupled to said            fixed base unit, comprising said current medical instrument;            said first detachable body unit is adapted for laparoscopic            surgery of a first modality;    -   b. coupling said first detachable body unit to said fixed base;    -   c. providing independent movements to said current medical        instrument selected from a group consisting of rotation and        translation; thereby performing said laparoscopic surgery of        said first modality with said first detachable body unit;    -   d. providing a second detachable body unit adapted for        laparoscopic surgery of a second modality;    -   e. decoupling said first detachable body unit from said fixed        base;    -   f. coupling said second detachable body unit for laparoscopic        surgery of a second modality;    -   g. performing laparoscopic surgery of said second modality with        said second detachable body unit; thereby altering the modality        of said laparoscopic surgery.        It is a further object of the present invention to disclose an        interface between a surgeon and an automated assistant,        comprising (a) at least one array comprising N RF transmitters,        where N is a positive integer; (b) one RF receiver, provided        with at least one directional antenna; (c) means for attaching        said RF transmitter array to at least one surgical tool;        and, (d) a computerized operating system adapted to record the        received signal strength (RSS) received by said RF receiver and        to calculate therefrom the position of each of said N RF        transmitters, and further adapted to provide automatically the        results of said calculation to the human operator of said        interface. It is within the essence of the invention wherein        said computerized operating system calculates at least one of        the parameters chosen from the group consisting of.        (a) the angle from which the signal had been received; (b) the        spatial location of said at least one surgical tool; (c) the        path of said at least one surgical tool; (d) the spatial        location of the point of insertion of said at least one surgical        tool into the body of a patient; (e) the spatial location of the        tip of said at least one surgical tool; (f) matching each RF        transmitter code with each calculated spatial location of said        at least one surgical tool and/or said tip of said at least one        surgical tool, and further wherein said computerized operating        system provides automatically the results of said calculation to        the human operator of said interface.

It is a further object of this invention to disclose such an interface,further comprising an endoscopic device.

It is a further object of this invention to disclose such an interface,wherein said endoscopic device comprises optical imaging means, andfurther wherein said computerized operating system calculates at leastone of the parameters chosen from the group consisting of (a) thespatial location of said at least one surgical tool; (b) the path ofsaid at least one surgical tool;

(c) the spatial location of the point of insertion of said at least onesurgical tool into the body of a patient; (d) the spatial location ofthe tip of said at least one surgical tool; (e) matching each RFtransmitter code with each calculated spatial location of said at leastone surgical tool and/or said tip of said at least one surgical tool;(f) the predicted appearance of said at least one surgical tool withinsaid optical image; (g) if more than one of said at least one surgicaltools appears simultaneously in said optical image, distinguishing amongsaid more than at least surgical tools appearing in said optical image,and further wherein said computerized operating system providesautomatically the results of said calculation to the human operator ofsaid interface.

It is a further object of this invention to disclose such an interface,further comprising (a) a automated assistant for said endoscopic device;and (b) means for interfacing said computerized operating system to saidautomated assistant. It is within the essence of the invention whereinsaid computerized operating system calculates at least one of theparameters chosen from the group consisting of (a) the spatial locationof said at least one surgical tool;

(b) the path of said at least one surgical tool; (c) the spatiallocation of the point of insertion of said at least one surgical toolinto the body of a patient; (d) the spatial location of the tip of saidat least one surgical tool; (e) matching each RF transmitter code witheach calculated spatial location of said at least one surgical tooland/or said tip of said at least one surgical tool; (f) a desired newlocation for said endoscopic device; (g) command protocol means fordirecting said automated assistant via said interface to maneuver saidendoscopic device to a desired new location, and further wherein saidcomputerized operating system provides automatically the results of saidcalculation to the human operator of said interface.

It is a further object of this invention to disclose such an interface,wherein said endoscopic device comprises optical imaging means, andfurther wherein said computerized operating system calculates at leastone of the parameters chosen from the group consisting of (a) thespatial location of said at least one surgical tool; (b) the path ofsaid at least one surgical tool; (c) the spatial location of the pointof insertion of said at least one surgical tool into the body of apatient; (d) the spatial location of the tip of said at least onesurgical tool; (e) matching each RF transmitter code with eachcalculated spatial location of said at least one surgical tool and/orsaid tip of said at least one surgical tool; (f) the predictedappearance of said at least one surgical tool within said optical image;(g) if more than one of said at least one surgical tools appearssimultaneously in said optical image, distinguishing among said morethan at least surgical tools appearing in said optical image; (h) adesired new location for said optical imaging means; (i) a commandprotocol for directing said automated assistant via said interface tomaneuver said endoscopic device to a desired new location, and furtherwherein said computerized operating system provides automatically theresults of said calculation to the human operator of said interface.

It is a further object of this invention to disclose such an interface,wherein said computer controller additionally transmits a commandprotocol to said automated assistant via said interface to maneuver saidendoscopic device to a desired new location.

It is a further object of this invention to disclose such an interface,wherein said interface is adapted for manual operation, whereby each ofsaid N transmitters transmits in response to a command signal from thehuman operator of the interface.

It is a further object of this invention to disclose such an interface,wherein said interface is adapted for automatic operation, whereby eachof said N transmitters transmits continuously.

It is a further object of this invention to disclose such an interface,wherein said interface is adapted for automatic operation, whereby eachof said N transmitters transmits continuously and further wherein saidcomputer transmits said calculated parameters for each of said Ntransmitters in response to a command signal from the human operator ofthe interface.

It is a further object of this invention to disclose such an interface,wherein said antenna array comprises at least one directional antenna.

It is a further object of this invention to disclose such an interface,wherein said transmitters transmit in the 430 MHz ISM band.

It is a further object of this invention to disclose such an interface,wherein M=1, and further wherein said receiver array is adapted todetermine the angle whose vertex is the location of said antenna arrayand which is subtended by the line connecting any two of said Ntransmitters.

It is a further object of this invention to disclose such an interface,wherein said interface comprises M receivers, M is an integer higherthan 1; and further wherein said M receivers are adapted to determinethe location of each of said N transmitters by triangulation.

It is a further object of this invention to disclose such an interface,wherein said transmitters transmit a modulated signal, said modulationchosen from the group consisting of (a) frequency modulation, (b)amplitude modulation.

It is a further object of this invention to disclose such an interface,wherein said modulation occurs at a frequency of about 1.5 kHz.

It is a further object of this invention to disclose such an interface,wherein each of said N RF transmitters is modulated at a differentfrequency.

It is a further object of this invention to disclose such an interface,wherein said N modulation frequencies are chosen from the band offrequencies spanning the range of from about 1.0 kHz to about 1.5 kHz.

It is a further object of this invention to disclose such an interface,wherein receiver is a single conversion receiver.

It is a further object of this invention to disclose a method forcalculating positional parameters of a laparoscopic surgical tool,comprising the steps of (a) obtaining an interface for a laparoscope,said interface comprising (i) at least one array comprising N RFtransmitters, where N is a positive integer, (ii) one RF receiverprovided with at least one directional antenna; (iii) a computerizedoperating system adapted to record the received signal strength RSSreceived by each antenna of said RF receiver and to calculate therefromthe position of each of said N RF transmitters, and further adapted toprovide automatically the results of said calculation to the humanoperator of said interface; (b) obtaining a surgical tool; (c) attachingsaid RF transmitter array to said surgical tool; (d) measuring thereceived signal strength (RSS) from said N RF transmitters received ateach of said directional antenna of said RF receivers; and (e)calculating spatial parameters relating to each of said N transmittersaccording to a

predetermined protocol. It is in the essence of the invention whereinsaid step of calculating said parameters of each of said N transmittersyields positional parameters of said laparoscope surgical tool, saidpositional parameters is selected from a group consisting of (a) theangle from which the signal had been received; (b) the spatial locationof said at least one surgical tool; (c) the path of said at least onesurgical tool; (d) the spatial location of the point of insertion ofsaid at least one surgical tool into the body of a patient; (e) thespatial location of the tip of said at least one surgical tool; (f)matching each RF transmitter code with each calculated spatial locationof said at least one surgical tool and/or said tip of said at least onesurgical tool, and further wherein said computerized operating systemprovides automatically the results of said calculation to the humanoperator of said interface.

It is a further object of this invention to disclose a method forcontrolling the position of an endoscopic device, comprising the stepsof (a) obtaining an interface between a surgeon and an automatedassistant, said interface comprising (i) at least one array comprising NRF transmitters, where N is a positive integer, (ii) one RF receiverprovided with at least one directional antenna; (iii) a computerizedoperating system adapted to record the received signal strength RSSreceived by each antenna of said RF receiver and to calculate therefromthe position of each of said N RF transmitters, and further adapted toprovide automatically the results of said calculation to the humanoperator of said interface; (iv) an automated assistant for saidendoscopic device; and, (v) means for interfacing said computerizedoperating system to said automated assistant; (b) obtaining a surgicaltool; (c) attaching said RF transmitter array to said surgical tool; (d)measuring the received signal strength (RSS) from said N RF transmittersreceived at each of said directional antenna of said RF receivers; (e)calculating spatial parameters relating to location of each of said Ntransmitters; (f) calculating a desired new position for said endoscopicdevice; (g) sending a command from said computerized operating system tosaid automated assistant via said interfacing means to maneuver saidendoscopic device to said desired new location; and, (h) maneuveringsaid endoscopic device to said desired new location

It is in the essence of the invention wherein said step of calculatingsaid parameters of each of said N transmitters yields positionalparameters of said laparoscope surgical tool, said positional parametersis selected from a group consisting of (a) the angle from which thesignal had been received; (b) the spatial location of said at least onesurgical tool; (c) the path of said at least one surgical tool; (d) thespatial location of the point of insertion of said at least one surgicaltool into the body of a patient; (e) the spatial location of the tip ofsaid at least one surgical tool; (f) matching each RF transmitter codewith each calculated spatial location of said at least one surgical tooland/or said tip of said at least one surgical tool, and further whereinsaid computerized operating system provides automatically the results ofsaid calculation to the human operator of said interface.

It is a further object of this invention to disclose such an interface,wherein said endoscopic device comprises optical imaging means, andfurther comprising the additional steps of (a) determining said positionof said surgical tool relative to the image frame; and (b) maneuveringsaid optical imaging means such that said surgical tool appears at apredetermined location within said image frame.

It is a further object of this invention to provide such a method,wherein each of said N transmitters transmits in response to a signalfrom the human operator of said interface.

It is a further object of this invention to provide such a method,wherein each of said N transmitters transmits continuously.

The device of the present invention has many technological advantages,among them simplification of the communication interface between surgeonand automated assistants; seamless interaction with conventionalcomputerized automated endoscope systems; simplicity of construction;reliability; and user-friendliness. Additional features and advantagesof the invention will become apparent from the following drawings anddescription.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following description is provided to enable any person skilled inthe art to make use of said invention and sets forth the best modescontemplated by the inventor of carrying out this invention. Variousmodifications, however, will remain apparent to those skilled in theart, since the generic principles of the present invention have beendefined specifically to provide a two-part endoscopic surgical devicewhich is composed of a positioning section (namely theendoscope/laparoscope) and a fixed section (e.g., tubular arm) coupledto the bed of the patient. The core concept of the present inventionlies in the fact that the positioning section may be removed entirelyfrom the fixed section e.g. for replacement, repair, cleaning, etc. Itwill be apparent to one skilled in the art that there are severalembodiments of the invention that differ in details of construction,without affecting the essential nature thereof, and therefore theinvention is not limited by that which is illustrated in the figures anddescribed in the specification, but only as indicated in theaccompanying claims, with the proper scope determined only by thebroadest interpretation of said claims.

The present invention provides a two-part robotic device used forexchanging the current medical instrument in used during laparoscopicsurgery. The device comprises (a) a fixed base unit; and (b) adetachable body unit reversibly coupled to said fixed base unit,comprising said current medical instrument.

It is emphasized that the detachable body unit is removable andreplaceable from said fixed base unit such that said current medicalinstrument is altered.

The present invention provides a method for exchanging a current medicalinstrument in used whilst performing a laparoscopic surgery. The methodcomprises steps of:

(a) providing a two-part robotic device comprising:

-   -   (i) a fixed base unit;    -   (ii) a detachable body unit reversibly coupled to said fixed        base unit, comprising said current medical instrument;        (b) coupling said detachable body unit to said fixed base;        (c) performing said laparoscopic surgery;        (d) detaching said detachable body unit from said fixed base        unit; and,        (e) replacing said current medical instrument in said detachable        body unit thereby exchanging said current medical instrument.

In the following detailed description, numerous specific details are setforth in order to provide a thorough understanding of embodiments of thepresent invention. However, those skilled in the art will understandthat such embodiments may be practiced without these specific details.Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment of the invention.

As used herein, the term “gear ratio” in a transmission with an inputshaft and an output shaft refers to the ratio of angular velocity of theoutput shaft to that of the input shaft.

As used herein, the term “transmission means” refers to means fortransferring torque from one rotating element to another, such asgearwheels, wheels, crown gears, and the like.

As used herein, the terms “endoscope” and “laparoscope” referinterchangeably to a fiber optical device that consists of a flexibletube. Glass or plastic filaments allow total internal reflection oflight for viewing. This medical device is used in laparoscope,endoscope, laparoscopic and endoscopic surgeries. It is also in thescope of the invention wherein the terms refer also to any means forlooking within body cavities, especially inside the human body andmammalian body for medical reasons using an instrument; and especiallyto means for minimally invasive diagnostic medical procedure, such asrigid or flexible endoscopes, fiberscopes, means for robotic surgery,trocars, surgical working tools and diagnosing means etc.

As used herein, the terms “endoscopic surgery” and “laparoscopicsurgery” interchangeably refer to a modern surgical technique in whichoperations upon the body of a patient, e.g., within the abdomen, areperformed through small incisions (usually 0.5 to 1.5 cm) as compared tolarger incisions needed in traditional surgical procedures. Laparoscopicsurgery includes e.g., operations within the abdominal, pelvic or jointcavities. Endoscopic surgery involves, inter alia, operations in thegastrointestinal tract, e.g., in the esophagus, stomach and duodenum(esophagogastroduodenoscopy), small intestine, colon (colonoscopy,proctosigmoidoscopy), bile duct, endoscopic retrogradecholangiopancreatography (ERCP), duodenoscope-assistedcholangiopancreatoscopy, intraoperative cholangioscopy, the respiratorytract, the nose (rhinoscopy), the lower respiratory tract(bronchoscopy), the urinary tract (cystoscopy), the female reproductivesystem, the cervix (colposcopy), the uterus (hysteroscopy), theFallopian tubes (falloscopy), normally closed body cavities (through asmall incision), the abdominal or pelvic cavity (laparoscopy), theinterior of a joint (arthroscopy) organs of the chest (thoracoscopy andmediastinoscopy), the amnion during pregnancy (amnioscopy), the fetus(fetoscopy), plastic surgery, panendoscopy, laryngoscopy, esophagoscopy;and various nonmedical uses for endoscopy. The term also refers to anymanipulation of laparoscopes and endoscopes as defined above into thebody of a patient.

As used herein, the term “degrees of freedom” (DOF) refers hereinafterto a set of independent displacements that specify completely thedisplaced position of the endoscope or laparoscope as defined above. Inthree dimensional space, there are six DOF, three DOF of lineardisplacement and three rotational DOFs, namely, moving up and down,moving left and right, moving forward and backward, tilting up and down,turning left and right, tilting side to side. The present inventionrefers to a system essentially comprising means for providing a total ofat least seven DOF (i.e. DOF for components of a multiple-componentsystem, wherein at least a portion of the DOF of a given component areindependent of those of the other components of the system) selectedfrom any of those that will be described hereinafter.

As used herein, the term “distal portion” refers to the end of theendoscope designed to be located within the body of the patient whilethe endoscope is in use, and the term “proximal portion” to the end ofthe endoscope designed to be located outside the body of the patientwhile the endoscope is in use.

As used herein, the term “base unit” refers to a rigid unit attached toa fixed point in space such as the floor, ceiling, surgical table, orthe like. The base is adapted to attach to a laparoscope and transmitvarious necessary elements to and from it including torques, light,voltages, video signals, and fluids.

As used herein, the term “body unit” refers to a laparascopic surgicalinstrument adapted to attach to a base unit. The base unit providesphysical support to the body unit, which must be able to maneuver inseveral dimensions and with several degrees of freedom. The base unittransmits various necessary elements to the body unit such as torques,voltages, fluids, etc. The body unit generally comprises a laparoscopicinstrument and various positioning devices used to change its positionand direction.

As used herein, the term “automated assistant” refers to any mechanicaldevice (including but not limited to a robotic device) that can maneuverand control the position of a surgical or endoscopic instrument, andthat can in addition be adapted to receive commands from a remotesource.

As used herein, the term “antenna gain” refers to the ratio of theradiation intensity of an antenna in a given direction to the intensitythat would be produced by a hypothetical ideal antenna that radiatesequally in all directions (isotropically) and has no losses.

As used herein, when referring to transmission of information to ahuman, the term “provide” refers to any process (visual, tactile, orauditory) by which an instrument, computer, controller, or any othermechanical or electronic device can report the results of a calculationor other operation to a human operator.

As used herein, the term “automatic” or “automatically” refers to anyprocess that proceeds without the necessity of direct intervention oraction on the part of a human being.

Laparoscopic surgery, also called minimally invasive surgery (MIS),bandaid surgery, keyhole surgery, or pinhole surgery is a modernsurgical technique in which operations in the abdomen are performedthrough small incisions (usually 0.5-1.5 cm) as compared to largerincisions needed in traditional surgical procedures. The key element inlaparoscopic surgery is the use of a laparoscope, which is a deviceadapted for viewing the scene within the body, at the distal end of thelaparoscope. Either an imaging device is placed at the end of thelaparoscope, or a rod lens system or fiber optic bundle is used todirect this image to the proximal end of the laparoscope. Also attachedis a light source to illuminate the operative field, inserted through a5 mm or 10 mm cannula or trocar to view the operative field. The abdomenis usually insufflated with carbon dioxide gas to create a working andviewing space. The abdomen is essentially blown up like a balloon(insufflated), elevating the abdominal wall above the internal organslike a dome. Within this space, various medical procedures can becarried out. Thus more advanced laparoscopes perform more than visualinspection, for instance performing various surgical procedures such ashernia repair, prostatectomy, liver resection, gastrectomy, and thelike.

Generally the laparoscope is held fixed in some fashion, either by anassistant, or on a mechanical support such as a gantry, stand, or thelike. For each laparoscopic procedure, in general a differentlaparoscope is required. Due to the specialized nature of theseinstruments, the support fixture for the device is generally specific tothe device and provided with it as a unit. In order to save space,expense, and complexity, the present invention provides a base unit thatis rigidly supported. This base unit in turn provides rigid support tothe laproscope. The laparoscope is detachable from the base unit in amodular fashion. Thus other laparoscopic instruments can be attached tothe same base station for carrying out different surgeries. The basestation is provided with the necessary fixtures to allow operation of avariety of laparoscopes, as will be detailed in the following.

For the performance of increasingly complex medical procedures, a systemfor transmitting a large number of mechanical degrees of freedom to theproximal end of a laparoscope is desirable. The present invention solvesthis problem within the constraints dictated by the nature oflaparoscopic surgery, namely a small incision diameter, a large distancebetween actuators (outside the body) and actuated elements (within thebody), and the desire to provide the laparoscope with as manyindependent degrees of freedom as possible.

The present invention provides a rigidly mounted base station and adetachable body unit comprising a laparoscopic surgical device. The mainadvantage in such a detachable body unit lies in the fact that the fixedunit remains in place while the detachable body (comprising the medicaltool to be used) can be altered quickly and easily.

Another key problem to be solved in laparoscopic surgeries is providingthe laparoscope with sufficient degrees of freedom. In the device of thecurrent invention this is solved using a novel N-DOF (n degrees offreedom) torque transmitter based on a coaxial constant-velocity joint.This joint will be described in the following.

First we'll describe the coaxial constant-velocity joint and then thecoupling of such joint in a laparoscope for providing said N-DOF.Lastly, the two-part robotic device comprising a medical instrument(e.g. an endoscope integrated within it said coaxial constant-velocityjoints).

The N-DOF torque transmitter is provided with a series of arms thatcontain multiple coaxial cylinders, each of which can rotateindependently. A novel joint allows two such cylindrical devices to bemated while transmitting the rotations of the coaxial members, allowingthe two cylindrical devices to be pivoted with respect to one another.The notion of concentric cylindrical members is simple enough to foregodetailed discussion, and thus in the following we concentrate on thedesign of the joint joining two such cylindrical members.

In many mechanical systems there arises the need to transfer torque froman input shaft to an output shaft. A wide variety of gear systems havebeen devised for this purpose. In a number of important cases the outputshaft must vary the direction of its axis with respect to the inputshaft. This is the case for example in a front-wheel-drive car. Theengine must provide torque to the wheels, to move the car forward.However the front wheels must also be allowed to change their axis ofrotation, to allow steering of the car.

The so-called universal joint, aka U-joint, Cardan joint, Hardy-Spicerjoint, or Hooke's joint is often employed for purposes of allowingvariation of the output axis direction. This is a joint in a rigid rodthat allows the rod to bend’, and is commonly used in shafts thattransmit rotary motion. It consists of a pair of ordinary hinges locatedclose together, but oriented at 90° relative to each other. See FIG.1A-1D for illustrations of this common joint. The concept of theuniversal joint is based on the design of gimbals, which have been inuse since antiquity.

There are several known drawbacks to the simple U-joint. When the twoshafts are at an angle other than 180° (straight), the driven shaft doesnot rotate with constant angular speed in relation to the drive shaft;as the angle approaches 90° the output rotation gets jerkier (andfurthermore, when the shafts reach the 90° perpendicular situation, theylock and will not operate at all). We note that our measurement of anglebetween output and input shaft is consonant with standard mathematicalpractice. Namely, when the input and output shaft are parallel in the‘unbent’ configuration, the angle between them is 180°. As the outputshaft is bent, this angle decreases until reaching 90° when the shaftsare perpendicular, and 0° when the output shaft is bent back upon theinput shaft.

Joints have been developed utilizing a floating intermediate shaft andcentering elements to maintain equal angles between the driven anddriving shafts, and the intermediate shaft. This overcomes the problemof differential angles between the input and output shafts.

The CV joint or constant velocity joint finds actual use in automotiveapplications. As shown in FIG. 2A this is a joint connecting the inputaxle 201 to the output axle 205. The splines 204 spin the spokes 209which in turn spin the plurality of ball bearings 202 on the inner ballrace 203. These balls are confined between the ball cage 206 and theouter socket 207, which has depressions 210 into which the balls fit.Since the balls are confined by both axles, they transfer the torquefrom the input axle 201 to the output axle 205. An isometric view isgiven in FIG. 2B. The two main failures are wear and partial seizure.Furthermore it will be appreciated that extreme angles between input andoutput shafts of around 90 or less will not be capable of transferringtorque at all, and in practice a continuous angle of about 100° degreesis the highest deviation from the straight 100° configuration obtainablewith a CV joint.

The double Cardan or double U-joint allows for a constant velocity to beattained at the output shaft, unlike the single U-joint. An improvementon this is two Cardan joints assembled coaxially where thecruciform-equivalent members of each are connected to one another bytrunnions and bearings which are constrained to continuously lie on thehomokinetic plane of the joint. This is the basis of US patentapplication 20060217206. Therein is disclosed a constant velocitycoupling and control system therefore, the so-called ‘Thompsoncoupling’, as shown in FIG. 3. A recent innovation, the Thompsoncoupling is a further development of the double Cardan-joint, whichdoesn't rely on friction or sliding elements (as the CV joint does) tomaintain a strict geometric relationship within the joint, and which iscapable of transmitting torque under axial and radial loads with lowfrictional losses. This coupling has all loads carried by rollerbearings, with no sliding or skidding surfaces whatsoever. It cantolerate axial and radial loads without degradation, with no wearingcomponents except replaceable bearings and trunnions, and is less bulkythan a double Cardan joint. However as will be appreciated from FIG. 3,this is a rather complex affair. Furthermore the maximum allowableangles are still restricted to a small range around 180°, e.g. to aninstantaneous minimum allowable angle of 155° and minimum continuousangle of 168°.

According to a preferred embodiment of the present invention, a methodis provided that allows the transfer of torque from an input shaft to anoutput shaft, whose axis of rotation may be varied continuously fromnearly 0 degrees to nearly 360 degrees with respect to the axis ofrotation of the input shaft.

With reference to FIG. 4 a representative embodiment of the invention isdetailed. The input shaft 401 is rotated due to torque from someexternal source. This torque is transmitted to spur gear 402. Spur gear402 engages crown gear 403, which therefore rotates and transmits torqueto spur gear 404. It will be appreciated by one skilled in the art thatthe spur and crown gears could be replaced with bevel gears. This simplearrangement is well known in the form of the bevel gear reversingmechanism. The key inventive step of the present invention is to allowthe output shaft 405 to rotate not only about its own longitudinal axisbut also about the axis 406. This is accomplished in the embodimentshown by coupling the output shaft 405 to axis 406 with a coupling thatallows relative rotation of the output shaft 405 around axis 406. Itwill be appreciated that with this device, the output shaft 405 can berotated in nearly a full circle around the axis 406 with no variation inthe torque provided.

In FIG. 5 the same embodiment is shown in plan view. Torque istransmitted from an external source to input shaft 401 and from there togearwheel 402. Gearwheel 402 engages crown gear 403, which thereforerotates and applies torque to gearwheel 404. The output shaft 405 isthus caused to rotate. The crux of the invention lies in the extradegree of freedom allowed to the output shaft 405, namely that it mayalso rotate about the axis of the crown gear 403, this being the keyprovision of the invention. Axis 406 is preferentially but notnecessarily largely collinear with the rotational axis of the planetarygear 403. Since the sizes of the gearwheels 402, 404 may be varied, thecoupling as a whole can be made to provide a gear reduction orenlargement, with correspondingly greater or smaller output torque, andcorrespondingly smaller or greater rate of angular rotation.

It should be noted that due to the symmetry of the device, torque canalso be transmitted in the opposite direction, from what we have calledthe output shaft to what we have called the input shaft. The terms‘output’ and ‘input’ are therefore somewhat misleading since either canbe used for output or input. Furthermore it will be appreciated that thechange of the axis of rotation of output with respect to input is arelative one, and that therefore the input axis of rotation can be movedinstead of the output axis of rotation, or both may be allowed to rotatewith respect to a stationary coordinate system. This is more than simplya matter of nomenclature; the effect can be used for instance totransmit feedback. For example, an actuator can be used to move acertain object, and a sensor can be attached to this object such thatthe degree of movement achieved is transmitted back to the operator ofthe device. A felicitous coaxial arrangement for such an implementationrequiring several simultaneous degrees of freedom is described in thefollowing.

It is within the scope of the invention to allow for multiple coaxialinput and output shafts to be employed simultaneously. With reference toFIG. 6 an example of such an embodiment is given in isometric view. Theinput shafts 611,612,613 are all collinear. They may be independent ordependent, as will be determined by the configuration of keyways andshafts such as 617,618 that can couple two input shafts or two outputshafts such that they rotate together. The output shafts 614,615,616 arerigidly coupled to output couplings 604,603,602 respectively andtherefore rotate with them. These output couplings are caused to rotateby means of crown couplings 605,606,607 respectively. The crowncouplings are caused to rotate by means of input couplings 608,609,610respectively. These input couplings are rigidly attached to input shafts611,612,613 and therefore rotate with them. The key provision of theinvention lies in the ‘extra’ degree of freedom available to the outputshafts 614,615,616 which can rotate along with output couplings604,603,602 around the axis 620. The axial support pin 601 fits intotrack 618 and travels with the output shafts, supporting them againstaxial loading. The radial support pin 621 supports the output shaftsagainst radial loading.

A further provision of the invention is for locking of individual axes.In FIG. 6 one sees that bolts 622 have been introduced which lock theoutermost input shaft to the body of the coupling. Therefore any attemptto rotate this input shaft will result in a rotation of the entirecoupling. Similar bolts can be added to the output shafts as well,allowing the coupling to be rotated around the axis of the output shaft.Finally, the crown couplings 605,606,607 can also be locked to the base623 of the device. By so doing, the direction of the output shafts canbe changed, as can the disposition (in the sense of angular orientation)of the entire joint itself.

It is within provision of the invention that the aforementioned bolts bereplaced with coupling elements such as linear actuators,electromagnets, and the like. It will be obvious to one skilled in theart that such coupling elements can be so constructed that they coupleor decouple electronically, allowing a further level of control over thedevice.

In FIG. 7 one sees and alternative embodiment of the device withmodified mechanical dimensions. In this figure the modularity of thecoupling is evident; the output shafts have been removed from the deviceand can now be replaced by a different output shaft (suitable for adifferent surgery, for instance). The output shaft (not seen) attachesto the output flange 701.

A similar embodiment is shown in FIG. 8, where both input and outputshafts have been removed. This would allow (for instance) the couplingas a whole to be cleaned.

In FIG. 9 A, B isometric views of an embodiment of the joint are shown.A gear lock bar 910 is seen. This gear lock bar serves to lock certaingears of the device in place, in place of the bolt 622 of FIG. 6. Thegear lock bar allows (for example) a surgeon to lock the output shaftinto a desired direction.

In FIG. 10 an exploded view of the joint of a joint of the device of thecurrent invention is shown. Input concentric cylinders 902 attach to theinput flange 903. This flange is rigidly coupled to coupling orientationgears 904, 905. Bolts 906 can be used to couple the flange to a rigidsurface. The input bevel gears 907 communicate torque to the crown gears909, which in turn communicate this torque to the output bevel gears911. These output bevel gears 911 are in communication with the outputconcentric cylinders 913. Bearing/stay 908 keep the crown gears 909 inplace. The gear lock 910 allows the angle of the output shaft withrespect to the input shaft to be locked. It should be emphasized thatthe input and output shafts 902, 913 can be detached from theirrespective flanges (902,912) if necessary, allowing different sectionsof the device to be removed or replaced.

In FIG. 11A the gear lock release is seen; a button 950 is depressed torelease the gear lock and allow the output shaft 952 to be rotated withrespect to the input shaft 951. In FIG. 11B another view is givenallowing one to note the large angular range of the output shaft, movingfrom position 952 a to position 952 b.

In FIG. 12A-D the shaft lock is shown in greater detail. The shaft lock910 can either allow or disallow free rotation of the shaft gear 905,thereby allowing or disallowing repositioning of output axis withrespect to the input axis.

It will be noted by the astute observer that the output axis of rotationof the instant invention can rotate in a single plane only if one doesnot use the aforementioned provision of bolts or output shaft lock(s) toallow for rotation of the coupling mechanism itself. However as will beclear to one versed in the art, this restriction can be removed by thesimple expedient of providing one or more further identical joints ofthe instant invention in series with the first, as shown in FIG. 13,where three joints 801,802,803 have been coupled in series. Anembodiment with two or more joints in series provides a nearly fullrange of motion of the output shaft, in all directions relative to theinput shaft. The only restriction on the angles is that the variousshafts cannot physically overlap any other shaft, thus eliminatingcertain configurations from the realm of possibility. It will beappreciated however that the disallowed positions form a smallproportion of the total universe of possibilities. This is especiallyrelevant when considering that the possible input-output angles of e.g.single or double Cardan joints are restricted to small angles of around168 degrees or less.

It will be appreciated that the gear ratio between input and outputshafts can be varied by variation of the size of the wheels orgearwheels of the couplings. In particular, if the input and outputgearwheels have radii ri, r₃ then the total gear ratio will be ri/r₃.

The constant velocity joint of the instant invention comprises:

-   -   i. An input shaft adapted to be rotated around an input axis of        rotation (the longitudinal axis of the shaft) by a sources of        torque.    -   ii. An input transmission means, coupled to one of said input        shaft, said input transmission means defining a first plane        substantially perpendicular to said input axis of rotation. The        input transmission means may for instance be a spur gear.    -   iii. A second transmission means rotatably connected to said        input transmission means; said second transmission means        defining a second plane, such that said second plane is        substantially perpendicular to said first plane. The second        transmission means may comprise for instance a crown gear        meshing with the first spur gear.    -   iv. An output transmission means rotatably connected to said        second transmission means; said output transmission means        defining a third plane; said third plane being substantially        perpendicular to said second plane. The output transmission        means may comprise for instance a spur gear meshing with the        second transmission crown gear.    -   v. An output shaft, coupled to said output transmission means,        adapted to rotate around an output axis of rotation, said axis        of rotation being free itself to rotate.

It will be noted that the angle between said first input axis ofrotation and said final output axis of rotation may vary in an angularrange of about 0 to about 360 degrees.

The transmission means may be selected from a group consisting ofgearwheels, wheels, crown gears, bevel gears, or other means fortransmitting rotational motion, or combinations thereof.

In one embodiment of the invention an axial support member (601) isprovided, to provide axial support to the output shafts. Also a circulartrack (618) centered on the axis of rotation of said second transmissionmeans is provided, said axial support member being adapted to fit intosaid track and slide within it.

In one embodiment of the invention a radial support member (604) isfurther provided to provide radial support to the output shaft, saidradial support member being adapted to rotate in said second plane.

In one embodiment of the invention several coaxial input shafts arecoupled individually to several coaxial output shafts, allowingindependent transmission of torque from input to output on severalshafts simultaneously.

It should be appreciated that the output shafts may be coupled to a widevariety of devices, such as graspers, cutters, splicers, welders,force-feedback devices, robotic hands, and the like. In particular theuse of force-feedback devices to provide a ‘return signal’ by means ofone or more shafts will be found especially useful in microsurgery,robotics, and the like wherein it is desirable to have some feedbackconcerning the ‘feel’ of the work being done.

It should be pointed out that amongst other advantages of the instantinvention is the fact that the torque-providing elements that turn theinput shafts may be located rather distant from the location where thetorque is applied. This is especially important in such fields asarthroscopy, microsurgery, and robotics, wherein it is generallydesirable that the point at which delicate operations occur are ascompact as possible. Also the presence of motors on or near joints cancause unwanted extra weight, moments of inertia, and the like. Theinstant invention allows many sources of torque to be transmitted inparallel in a minimum of space limited only by the shaft wallthicknesses, and at a distance from the actual operations of the outputshafts that is in principle unlimited. No motors are required at thelocation of the joint itself, as in many current applications.

It should be further appreciated that the instant invention allows forthe actuating motors to be located in a central protected location suchas the abdomen of a robot, the center portion of a tank, etc. Thisfurther allows for a single motor to activate several input shaftsindependently. If for example it is discovered that in a particularapplication certain actions requiring rotation of shaft A preclude otheractions requiring rotation of shaft B, a single motor can be used toprovide the torque necessary for these actions, and switched from inputshaft A to input shaft B by a suitable gearbox as will be obvious to oneskilled in the art.

In one embodiment of the invention access is given to the crown gears ofthe device, in effect changing the device into a three-terminal or ‘T’or ‘Y’ device. In particular the central or crown gears 605, 606, 607(FIG. 6) may be connected to input/output shafts of their own. Now morecomplex operations may be allowed, wherein further couplings areconnected to this center shaft, or further torque sources, or furtheroutput devices such as graspers, cutters, and the like, or sensors.

We now turn to the incorporation of this coupling device into alaparoscopic instrument of improved design. In the prior art one finds alarge number of laparoscopic positioning systems such as those shown inFIGS. 14A-C. These will in general allow a small number of degrees offreedom, the maximum found in a search of the patent literature beingfive degrees of freedom.

To improve upon this situation while keeping the simple tubular designof the laparoscope intact, we incorporate the aforementioned couplingdevice into an endoscope/laparoscope maneuvering system as shown in FIG.15A, B.

The cylindrical members (consecutive arm sections) 995, 996, 997 and 998contain a plurality of concentric cylinders, each able to rotateindependently and thereby activate an independent degree of freedom. Bymeans of these concentric cylindrical members, the couplings (i.e., theconstant velocity couplers) 1002, 1003, 1004, 1005 and 1006 serve torotate/translate the device (namely the endoscope/laparoscope 1001 b orthe camera 1001 a) in the directions DOF₁ (1007), DOF₂ (1008), DOF₃(1009), DOF4 (1010), DOF₅ (1011), DOF6 (1012) and DOF₇ (1013), in whichDOF₁ represents the ability of the system to move the endoscope orlaparoscope forward and backwards in direction represented by numericalreference 1007, DOF2 represents the ability of the system to move theendoscope or laparoscope in a zoom movement i.e. in and out of thepatient body through the penetration point (represented by numericalreference 1008), DOF3 represents the ability of the system to move theendoscope or laparoscope to the right and left in direction representedby numerical reference 1009, DOF4 represents the ability of the systemto fine tune the endoscope or laparoscope movements to the right and tothe left in direction represented by numerical reference 1010, DOF5represents the ability of the system to fine tune the endoscope orlaparoscope movements forward and backwards in direction represented bynumerical reference 1011, DOF6 represents the ability of the system torotate the camera 1001 b with respect to the endoscope's 1001 a longaxis. This degree of freedom is necessary to keep the horizon of theimage when using endoscope with “angled edge,” and DOF7 represents theability of the robot to rotate the endoscope 1001 b about its long axis.

Views of the same device from the opposite direction are shown in FIGS.16A,B. Isometric views are shown in FIGS. 17A,B. Further side views areshown in FIG. 18A,B with a pencil included for scale.

FIG. 19 shows the main and the preferred embodiment of the presentinvention which incorporates the positioning elements of FIGS. 15-18upon a standardized tubular arm 1901. As described above, the coreconcept of the present invention lies in the fact that the positioningsection 1902 may be removed entirely from the fixed section (tubulararm) 1901 e.g. for replacement, repair, cleaning, etc.

In FIG. 20 illustrates a more complete embodiment, where two consecutivetubular members 1901, 1902 are employed. The lower tubular member 1902may for instance be fixed to the floor, ceiling, surgical table, or thelike. This tubular member is in certain embodiments endowed with one ormore cylindrical motors (which will be further explained in FIG. 22)within the body of the cylinder, adapted to turn a set of the concentrictorque-transmitting elements described above.

The second tubular member 1901 transmits these torques to the medicaltool to which he is coupled. It is within provision of the inventionthat one of these multiple torques can be used to rotate the uppertubular member 1901 about the coupling element 2004. It is also withinprovision of the invention that these two arms may be detached from oneanother. The upper tubular member 1901 may also be provided with one ormore internal cylindrical members such as shafts or motors to power thevarious operations of the laparoscope, including the various possiblemovements of the laparoscope positioning section 2003, and any surgicalinstruments attached to the end of the laparoscope tube 2005.

It is emphasized that the number of the consecutive tubular members isnot limited to two.

In FIG. 21 a cross section of the tubular sections shown in FIG. 20 isshown. In the cross section of FIG. 21 one can see the two motors 2101,2102 of the lower arm and the two motors 2103, 2104 of the upper arm.Each of the motors is adapted to provide movement in a specificdirection. For example, motor 2104 may be adapted to provide left andright movement; motor 2103 may be adapted to provide forward andbackwards movement; motor 2102 may be adapted to provide zoom in andzoom out movements; and, motor 2101 may be adapted to provide rotationalmovements.

In FIG. 22 an embodiment of the device is shown in use. The lower arm2201 is shown fixed to the operating table 2202. The upper arm 2203 mayrotate about the coupler between the upper and lower arms, while theseven degrees of freedom of the laparoscope positioning section 2204allow the laparoscope 2205 to be moved controllably in many ways, as maybe required during surgical procedures.

In actual use such a laparoscope as described above may be operatedeither manually by a human being, or robotically, according to aprogrammed set of instructions, by a robotic mechanism obeying humancommands, remotely, or the like. A robotic mechanism is shown in FIG.23A,B, In FIG. 23A,B, various possible motions of the device areillustrated.

In FIGS. 24A and 24B various possibilities for operation of the deviceare shown. In FIG. 24A a surgeon is shown operating using the device. Aswill be obvious to one skilled in the art the actuation may be carriedout using a variety of means such as joystick control, keyboard control,voice control, manual control, power-assisted control, or the like. InFIG. 24B the device is shown without a surgeon, who may in principlecontrol the movements of the device remotely, or in principle the devicemay be operated entirely algorithmically.

It is within the scope of the invention that the base and body units ofthe invention provide various desirable elements to allow complexsurgical procedures to be carried out, such as one or more fluidchannels, one or more electrical conductors, one or more fiber opticchannels, and the like. The fluid channels may provide e.g. CO2 forinflating a body cavity, saline solution for flushing, vacuum foraspirating blood, pus, or other bodily fluids, and the like. Theelectrical conductors may conduct voltages to operate various motors oractuators, conduct information from sensors such as video cameras orpiezoelectric gauges, and the like. The fiber optic channels may conductvisual information from the body or may provide light within the bodycavity. It is within provision of the invention that these variouselements be conducted in tubes threaded within the tubular structures ofthe current invention, or attached to the outsides thereof.

One skilled in the art will realize that the device described above hasthe potential to facilitate surgery by freeing one hand of the surgeonthat would otherwise have to grip the laparoscope.

It is further within the scope of the present invention to provide atwo-part robotic laparoscopic device useful for functional endoscopicsinus surgery (FESS). If the nasal sinuses become blocked for example bynasal polyps, growths, allergies or infection, causing great discomfort.The first line of treatment for sinus blockages is medical therapy,however in some cases this is unsuccessful and surgery is required.Sinus blockages are a common problem and sinus surgery is one of themost frequently performed, failure to treat sinus blockages can resultin facial pain, headaches and rarely, complications. Reference is nowmade to FIGS. 36 A-C, 37 and 41, illustrating several embodiments ofsinus surgery. FESS, allows the procedure to be performed as dayoperation, accessing the sinuses by inserting an endoscope through thenose and removing blockages in a relatively non-invasive manner,resulting in easier and quicker recovery and lower risks thantraditional sinus surgery. Thus FESS is a precise, minimally invasiveway to open your sinuses and treat chronic sinus infections. The presentinvention is provided to enable access of all areas of the sinus andnaval cavity with the endoscope, ensuring better treatment of theblockages.

As described above, according to another embodiment of the presentinvention to improve upon the interface between surgeon and automatedassistants by communicating the surgeon's current instrument of choice,supplying location data to the image processing computing softwarethereby directing the endoscope to focus on said choice. The technologyrelies on marrying a conventional laparoscopic system with data obtainedfrom small RF transmitters attached to a surgical tool.

The present invention provides an interface between a surgeon and anautomated assistant, comprising (a) at least one array comprising N RFtransmitters, where N is a positive integer; (b) one RF receiver, saidreceiver provided with at least one directional antenna; (c) means forattaching said RF transmitter array to at least one surgical tool; and,(d) a computerized operating system adapted to record the relativesignal strength received by said RF receiver and to calculate therefromthe position of each of said N RF transmitters, and further adapted toprovide automatically the results of said calculation to the humanoperator of said interface. It is within the essence of the inventionwherein said computerized operating system calculates at least one ofthe parameters chosen from the group consisting of (a) the spatiallocation of said at least one surgical tool; (b) the path of said atleast one surgical tool; (c) the spatial location of the point ofinsertion of said at least one surgical tool into the body of a patient;(d) the spatial location of the tip of said at least one surgical tool;(e) matching each RF transmitter code with each calculated spatiallocation of said at least one surgical tool and/or said tip of said atleast one surgical tool, and further wherein said computerized operatingsystem provides automatically the results of said calculation to thehuman operator of said interface.

In one of the preferred embodiments of the invention, any desiredsurgical instrument is fitted with an RF transmitter, and selection isachieved by depressing its button.

The invention discloses two methods of operation: a manual method, inwhich a transmitter emits an RF signal only when the surgeon presses abutton located e.g., on one of the arms (either left or right—but notboth simultaneously), the system then indicating the direction of thatarm, and an automatic method, in which all transmitters continuouslyemit RF signals and the system tracks the direction of all transmitterssimultaneously. When the surgeon presses a button of one of thetransmitters, the system output is the direction and location of thespecific transmitter.

The automatic mode has some advantages over the manual mode because thesystem can make use of history track files in order to filter the dataand apply prediction algorithms. The continuous stream of data alsoallows the software to compute additional important data such as theinsertion point of each tool, and the predicted tools location on theimage.

System operation will be explained for both MANUAL (sequential), andAUTOMATIC (periodic or simultaneous) modes. In order to simplify theexplanation a system used to locate the positions and directions of only2 surgical tools is described, but the method described can be used withminor changes to locate the position of any number of surgical toolsused in any laparoscopic surgeries.

Reference is now made to FIG. 25A which schematically describes thesurgical tool positioning MANUAL system according to one embodiment ofthe invention. An antenna 31 is set and a receiver is preferably mountedon, or near, the robotic camera holder. Two identical transmitters,i.e., (i) transmitter 11 mounted on surgical tool 10; and (ii),transmitter 21 mounted on surgical tool 20 are provided. A control andprocessing function controller 40 is further provided, being either alaptop PC or an embedded controller.

As described above, in the MANUAL system the transmitter emits RF signalonly when the surgeon presses upon the surgical instrument the surgeondesires to track. Once the transmitter transmits a signal, the receivercommunicates with the controller and instructs the tracking of themedical instrument desired by the surgeon.

Reference is now made to FIG. 25B which schematically describes thesurgical tools positioning AUTOMATIC system according to yet anotherembodiment of the invention.

As described above, in the AUTOMATIC system the transmitter continuouslyemits RF signals. Therefore, the receiver constantly communicates withthe controller.

The transmitters 11 and 21 can operate in one of three modes: (a)sequential/manual mode, as shown in FIG. 26a , upon the surgeon'spressing an appropriate button (manual mode); (b) periodic/automaticmode as shown in FIG. 26b , in which the transmitters attached to thetwo tools provide pulsed signals at different pulse rates; or (c)simultaneous/automatic mode, as shown in FIG. 26c , in which the twotransmitters transmit simultaneously and continuously, but at differentradio frequencies. In all three modes, the receiver can detect andprocess individual reception from any one of the two tools and identifywhich transmission belongs to which tool.

Reference is now made to FIGS. 27A, B, 28A through 28D, and 29, in whichfurther details of the system operation are illustrated. The receiverreceives sequentially the signal of each tool through the antenna set,the antenna set comprising at least one (preferably) multipledirectional antennas array as shown in FIG. 31A, where at least one ofthe antenna is connected to the receiver. In order to locate thetransmitter, at least two directional patterns are required asillustrated in FIG. 32A. The figure illustrates a typical antenna'spattern as a function of the signal's angle and of the intensity.

Alternatively, the transmitted signal may be modulated (in differentembodiments of the invention, either (a) frequency modulation or (b)amplitude modulation or (c) both FM and AM simultaneously). Thus, inorder to identify the arm from which the transmission is being received,each transmitter has a different modulation frequency. Hence an easierdetection of the arm is enabled. In general once the correct transmitterhas been identified, the following mathematical analysis is performed:

-   -   The direction of each transmitter (and hence the desired        instrument) is calculated by using a single receiver having at        least 3 directional antennas.    -   The received signal strength (RSS) is a function of the        distance (d) between the receiver and the transmitter (i.e., the        instrument); the strength of the transmitted signal (P); the        path loss exponent (11); and the antenna's gain (Gr).    -   Since all the antennae are co-located, the ratio of the RSS will        be the ratio between the antennas' gain.

Therefore, by knowing how the gain ratio varies with the angle—one cancalculate the angle from which the signal has been transmitted.

The above mentioned mathematical analysis id performed based on thefollowing facts:

The method uses several directional antenna that are co-located as a setof receiving antenna; and the transmitter is assumed to be locatedsomewhere around the receiving antenna set.

As described, the method is adapted to find only the direction of thetransmit antenna by comparing the received power from all antenna in theset. As commonly known, the received power depend on the transmit power(PT), the distance from receiving to transmit antenna (d) and on thereceiving antenna gain (Gr(i)) in the direction of the transmitter.Since the set of antenna are co-located (the transmit power (PT), thedistance from receiving to transmit antenna (d) et cetera areeliminated) and the ratio of the receiving signal strength (RSS) is asfollows:

RSS(antenna(i))−RSS(antenna(k))=Gr(antenna(i))−Gr(antenna(k))

As can be seen, the difference in the RSS does not depend upon thetransmit power PT (since the PT received by each antenna is the same),and it does not depend upon the distance (since the received antenna areco-located).

From the difference set of RSS, the difference in the gain between thereceiving antennas is known.

Since the receiving antennas are directional, the gain pattern isdependent only upon the angular positioning of the transmitter (andhence the instrument). Therefore, the angular position and hence thedirection can be resolved unambiguously from the gain difference, and itis therefore possible to calculated the angle from which the signal hasbeen transmitted from a measurement of how the gain ratio varies withthe angle (see FIG. 27B). As illustrated in FIG. 27B, once the RSSdifference is known, the angle from which the signal is being sent(i.e., the angular location of the transmitter and hence the instrument)can be calculated.

It should be noted that the above mentioned calculation is much lesssensitive to multipath environment found whilst applying the methods inlaparoscopic surgeries.

According to another embodiment of the invention, the antenna array hasmore than two patterns, allowing the system to identify the direction ofthe tool with a finer resolution. Reference is now made to FIG. 31B, inwhich a non-limiting example of an additional embodiment is illustrated,in which the antenna array comprises four directional patterns: left,right, forward and aft. From the direction from which the strongestreception is received, the system is able to identify the sector inspace in which the tool is located. Moreover, from interpolation of thereceived power from all antenna patterns, even finer directionalresolution is possible.

The receiver detects the received signal power for each antenna in thearray and reports it to the controller. The controller then resolves thedirections of the two tools relative to antenna 31. Transmitters 11 and21 shown in FIG. 28A may transmit in a wide range of frequencies; atypical frequency is the ISM band of 430 MHz. Transmission is done atvery low power, generally below about 1 mW. The transmitted signal ismodulated (in different embodiments of the invention, either (a)frequency modulation or (b) amplitude modulation or (c) both FM and AMsimultaneously). In a preferred embodiment, the modulation is performedat an audio rate of about 1.5 kHz. The transmitter uses a built-inantenna. In order to identify the arm from which the transmission isbeing received, each transmitter has a different modulation frequency.In a preferred embodiment of the invention, the frequencies are locatedwithin the band encompassing the range of from about 1.0 kHz to about1.5 kHz.

The signal for each transmitter is received by all antennas in the array(see FIG. 28B above). The antennas in the array typically comprise threevery short dipoles mounted on the edge of an equal edge three-leggedstar or circle, as shown in FIGS. 31A and 31B. The diameter of thecircle or three-legged star is about 8 to 12 cm for operation at about430 MHz. The use of the antenna array to identify the beam pattern isillustrated schematically in FIG. 28B. The antenna pattern is formed bycombining the signal received by each antenna with different delays andsignal weights. In order to set the pattern, in a typical embodiment,each antenna output is split into several equal power signals and asample of each antenna signal is combined into one directional output.Which output is being measured is selected by an external switch.

The receiver receives the signal in sequence from each directionalpattern and detects the signal power in any pattern for the signals fromboth tools; from the power ratio the signal direction is calculated. Forexample, for a two pattern antenna (left and right) if the signal fromleft antenna is much stronger than from right one, then the signal musthave arrived from the left and vice versa. In parallel, the signalmodulation as transmitted is detected and the modulation frequency ismeasured. Since each transmitter has a different modulation frequency,identification of the transmitter from which a particular signaloriginates is straightforward.

The receiver may be of any type, but in order to reduce the cost, sizeand power consumption, in a preferred embodiment, the receiver is asingle conversion receiver that converts the input signal to base band.The receiver block diagram is shown in FIG. 28C. The receiver operationis as follows: the RF input is filtered around the transmitter frequencyband then passed through a variable attenuator controlled by the systemcontroller. Next, it is then amplified and then down converted using aQuadrate mixer and a local oscillator. The mixer outputs are the IFbaseband: I (in phase) and Q (Quadrate) outputs, which are filtered bytwo low pass filters (e.g., about 30 kHz) then amplified. The base bandsignal powers are then detected. The DC power relative to the signalpower is selected in sequence. The analog signal is then passed to ananalog to digital converter (ADC), following which the total receivedpower is computed digitally.

In an additional embodiment of the invention (not illustrated), the baseband signal is analog to digital converted, so that the power of boththe I and the Q channel is converted to a digital value. The localoscillator frequency is locked by the PLL to the XTAL referenceoscillator, controlled by the system controller. In order to ensure thatreceived signal is within a limited range the receiver gain is adjustedautomatically (AGC). Finally, as shown in FIG. 28d , the digital signalpower is transferred to the system controller, where the controllercalculates from the time of reception from which tool it is received andfrom which antenna pattern, using the power the controller compute thetool direction for each of the two tools.

The controller includes a timer based sequencer, preferably built intothe microprocessor timing unit, that switches the receiver antenna, andin case of multiple frequency transmission, sets the receiver frequencysequentially. The operation sequence of the system is illustratedschematically in FIG. 29, which shows the system control softwareoperation flow:

[1] The AD signal is averaged to detect the average amplitude, averagingbeing done over one dwell duration (“X” indicates the output afteraveraging);[2] Signal presence is detected when X is above a predeterminedthreshold;[3] Average amplitude X is saved in a vector array (Aver_A (n), n={1, 2,. . . N}) if signal is present, the storage being done on theappropriate antenna number place in the array;[4] If for a given antenna, signal is present on N successive dwelldurations, the signal direction is calculated;[5] The modulation (in the particular embodiment illustrated, AM) isdetected from the signal power input;[6] The modulation frequency is measured; and,[7] From the measured frequency, the arm type is detected; in the caseof weak signal or simultaneous transmission, the module reports “can'tdecide,” indicating a garbage signal.

In embodiments in which the transmitter operates periodically, bothtransmitters operate for a fraction of the time then switch off, thenswitch on again and so on with a constant or random cycle periodicity,each transmitter transmitting with a different transmission pulse cycletime in order to ensure that transmissions will not overlap at all timesbut only at times separated by t1·t2, where t1 and t2 are the pulsecycle times of the two transmitters. In parallel, the receiversequentially switches the receiver channel among the different antennasand dwells on each antenna for a fixed dwell time. From the level ofsignal received, the system determines whether or not a signal ispresent. If a single signal is present either from the right arm or leftarm transmitter, the direction of the signal is calculated from thesignal strength received from different antennas, and the arm isidentified from the internal modulation frequency. In case of coincidentsimultaneous transmit the receiver cannot identify the signal modulationtherefore the measurement is rejected. In an additional embodiment, thesystem tracks the transmission period cycle of each arm and predicts thesimultaneous transmission times in order better to identify which arm'ssignal is being detected.

In order to ensure that the direction of a single transmission can becalculated (if only a single transmission is received), the “transmiton” duration is at least (N+1) X dwell intervals, where N is the numberof antenna outputs. This ensures that the transmission is receivedduring at least N successive dwell times, allowing the system tocalculate its direction. For example if the receiver antenna is switchedin sequence staying on for 10 ms (i.e., a 10 ms antenna dwell time) ineach pattern out of two patterns, then the total antenna switch timecycle is 20 ms, and the transmitter switch on time is required to lastfor at least 30 msec. For example, in one embodiment of the invention,the transmit on/off cycle times are 120 ms and 150 ms for the left andright arm transmitter respectively. Each transmitter is on for 30 ms andoff for the rest of the time. The antenna switch versus transmitperiodic operation is shown in FIG. 30A.

In the case of sequential transmission, each transmitter should be onfor at least (N+1) X dwell intervals (receiver antenna dwell time). Theantenna switch versus transmit sequential operation is shown in FIG.30B.

In embodiments in which the two transmitters operate at differentfrequencies, the receiver scans all antenna patterns at the firstfrequency, then switches to the second frequency and scans all antennapatterns again, then returns to the first frequency, and so on.

Reference is now made to FIG. 31A, which illustrates an embodiment ofthe invention in which the directional antenna array has a planarstructure. The short dipoles at each segment 72 a,b,c are covered toprotect the wires and the circuits from humidity and mechanicalfractures. The arms 73 a,b,c are made of any appropriate flexiblematerial.

Reference is now made to FIG. 31B, which illustrates an embodiment ofthe invention in which the directional antenna array has a non-planarspatial structure. The fourth short dipole at segment 72 d is notlocated in the plane that contains segments 72 a,b,c. This arrangementallows the system to compute the spatial direction of the RFtransmitter.

Reference is now made to FIG. 31C, which shows the antenna located on anautomated assistant maneuvering system according to one embodiment ofthe invention.

Reference is now made to FIGS. 32A, B, C, which illustrate in anon-limiting manner some types of surgeries in which the location systemdisclosed in the present invention can be utilized.

FIG. 32A shows an example of using the location system in abdominallaparoscopic surgery.

FIG. 32B shows an example of using the location system in kneeendoscopic surgery.

In FIG. 33A-C another aspect of the invention is shown particularlysuited for sinus surgery.

Reference is now made to FIG. 34, which illustrates an additionalembodiment 420 of the invention herein disclosed. Surgical device 4201is held in position by robot end effector, which comprises a pluralityof shaft tubes 4204 (in the embodiment illustrated, there are 5 shafttubes 4204 a-4204 e) connected in series by a set of joints 4205. One ofsaid joints (in the embodiment shown, 4205 a) connects the first shafttube 4204 a to the body of the instrument, while another (in theembodiment shown, 4206) is attached the final shaft tube (in theembodiment shown, 4204 e) and comprises means (e.g. a closeable slot orhole) to hold the surgical device in a position fixed relative to thefinal shaft tube. Motor means for effecting movement of the shaft tubesis contained within motor box 4202, and the controller mechanisms arecontained with controller box 4203.

Reference is now made to FIG. 35A, which illustrates the various DOF andan external view of the means for connecting medical device 4300 to thecontrol unit according to an embodiment 430 of the invention. Accordingto this embodiment, 6 independent DOF are available to the medicaldevice (FIG. 35A): (1) rotation 4311 of the entire connecting meansabout the z-axis; (2) translation 4312 of the medical device along apredetermined axis within the x-y plane; (3) rotation 4313 of themedical device about the axis defined by 4312; (4) rotation 4314 of themedical device about an axis perpendicular to that defined by 4312; (5)rotation 4315 of the medical device about the z-axis; and (6)translation 4316 of the instrument along the z-axis. Motion about DOF4312-4316 is accomplished without gross movement of the entireconnecting means. As described in detail below, independent motionsalong these DOF are enabled by a system of n joints 4301 (in theembodiment shown, n=3; in other embodiments, n may be any positiveinteger) terminating in end joint 4303 and connected by a series of nshafts 4302. As illustrated in FIG. 35B, 4311 and 4312 can be considereda vector in the x-y plane and an angle in the x-y plane relative to thex-axis, respectively. Thus, 4311 and 4312 define the location of a pointin space through which the longitudinal axis of the medical device(which is located parallel to the z-axis) passes. This point in spacecan be thought of alternatively as the center of a bead 4320 throughwhich the medical device passes. As shown in FIG. 35C, rotations 4313and 4314 can be considered rotations of the bead about two mutuallyperpendicular axes in the x-y plane. FIG. 35D illustrates howtranslation 4315 and rotation 4316 are defined relative to the point4320.

Reference is now made to FIG. 36A, which illustrates means by whichmotion about DOF 4311 are accomplished according to one embodiment ofthe invention. Rotation is possible through any arbitrary angle 4311about rotation axis 4311 x, as illustrated schematically in FIG. 36A.The motions are enabled by a system of gears, as illustratedschematically in FIG. 36B. The first gear 4330 is mated to input shaft4302 i. Intermediate gear 4331 is mated to first gear 4330 and which inturn mated to a second gear 4332 that is rigidly connected to one end ofoutput shaft 4302 o and rotates around an axis substantially coincidentwith the longitudinal axis of the output shaft. A plurality of bolts4333 fix output shaft 4302 o to joint 4301 a.

Reference is now made to FIG. 37A, which illustrates means for enablingmotion about DOF 4312 and 4313. Illustrated in FIG. 37A is shaft 4302 a,which connects joints 4301 a and 4301 b. Also illustrated is internaltube 4313 a which contacts shaft 4302 a via bearing 4313 c. Asillustrated in FIG. 37B, this bearing allows joint 4301 a to rotatefreely about the longitudinal axis of external tube 4313 b (see FIG.38). Disposed about at least part of the outer surface of tube 4313 a isa threaded portion 4312 b, while a threaded portion 4312 a is disposedabout at least part of the inner surface of shaft 4302 a; the twothreaded regions are in contact such that controlled rotational motionof 4302 a relative to 4313 a is possible. The threaded regions are shownin more detail in FIG. 37C. When output gear 4332, which is rigidlyconnected to one end of tube 4313 a, rotates, threaded portion 4312 anecessarily rotates as well. A plurality of protrusions 4312 c disposedabout the outer surface of tube 4313 a and substantially parallel to itslongitudinal axis fit into matching grooves 4312 d disposed about theinner surface of shaft 4301 a (the protrusions and grooves are shown indetail in FIGS. 37D and 37E). Because of this protrusion/slot interface,rotation of output gear 4340 cannot lead to rotation of tube 4301 a.

Reference is now made to FIG. 38A, which illustrates means for enablingmotion about rotational DOF 4313 and the spatial relationships betweenthe components responsible for this motion and those responsible forindependent motion about DOF 4312. Once again, the portion connectingjoints 4301 a and 4301 b is illustrated. Output gear 4350 is rigidlyconnected to one end of external tube 4313 b (FIG. 38A) and rotatesabout an axis substantially coincident with the longitudinal axis of thetube. As illustrated in FIG. 38B, tubes 4313 a and 4313 b are locatedwithin shaft 4302 a, with longitudinal axes substantially coincident.FIGS. 38C and 38D illustrate translation along 4312 and the consequentmotions of tubes 4313 a and 4313 b. As illustrated in FIG. 38E, theouter surface of internal tube 4313 a and inner surface of external tube4313 b are not circular, but are rather designed to prevent freerotation of the inner tube with respect to the outer tube. In apreferred embodiment, the outer surface of inner tube 4313 a has asubstantially polygonal cross-section, and the inner surface of outertube 4313 b is machined substantially to match the shape of 4313 a. In amore preferred embodiment, the substantially polygonal cross-section issubstantially hexagonal. Other shapes are possible, e.g. facing off aportion of a substantially circular cross-section to provide a singleplanar surface, with the planar surfaces of the inner and outer tubescorresponding to prevent the possibility of free rotation of the innertube. By this means, rotation of 4313 b through an angle θ necessarilyleads to rotation of 4313 a through the same angle. As illustrated inthe figure, rotation through any arbitrary angle θ is possible for anyvalue of the translational extension 4312.

Reference is now made to FIG. 39A, which illustrates the relativemotions of DOF 4313-4316. As shown in FIG. 39A, all of the axes ofrotation of the distal link meet at point 4320. The rotation axesrelative to the long axis of medical device 4300 are illustrated in FIG.39B.

Reference is now made to FIG. 40, which illustrates means for enablingindependent motion about DOF 4314. Input gear 4314 b is rigidlyconnected to one end of internal tube 4314 a, with its axis of rotationsubstantially coincident with the longitudinal axis of 4314 a. Inputgear 4314 b is mated to intermediate bevel gear 4314 c, which in generalis not in the same plane. In the preferred embodiment illustrated in thefigure, the two gears rotate about axes that are substantiallyperpendicular. Intermediate spur gear 4314 d is substantially rigidlyconnected to, and rotates about substantially the same axis as, 4314 c,although, as illustrated in the figure, the ratio between the two gearsis not necessarily equal to 1. Intermediate spur gear 4314 d is mated todistal link 4314 e via interaction with a toothed portion of said distallink. Thus, rotation of internal tube 4314 a causes rotation of inputgear 4314 b, leading to rotation of intermediate bevel gear 4314 c andhence rotation of intermediate spur gear 4314 d, causing rotation ofdistal link 4314 e.

Reference is now made to FIGS. 41A-41E, which present a generalillustration of means for effecting motion about DOF 4315 and 4316. Themotions relative to the connection means are shown in FIG. 41A, and themeans for effecting motion of the medical device are illustrated in FIG.41B. Means for effecting motion about DOF 4315 comprise worm drive 4315a and worm gear 4315 b. As illustrated in FIG. 41C, worm gear 4315 b issubstantially ring-like in design, with the gear teeth disposed aboutthe outer circumference of the ring. The inner circumference of the ringcomprises a protrusion that is adapted to fit into a matching slot inthe outer circumference of, and substantially parallel to thelongitudinal axis of, rack 4316 a. Rack 4316 a is adapted to holdmedical device 4300. Means for effecting such holding are well known inthe art; as a non-limiting example, rack 4316 a may comprise a borealong its longitudinal axis, wherein said bore is of the proper diameter(possibly with stopping down) to provide a snug fit to medical device4300. Rotation of worm drive 4315 a about its axis leads to rotation ofworm gear 4315 b about its longitudinal axis, causing rotation of rack4316 a about its longitudinal axis, and thus causing medical device 4300within to rotate in proportion to the amount of rotation of the wormdrive. Translational motion about DOF 4316 is effected byrack-and-pinion means 4316 a and 4316 b. When pinion gear 4316 brotates, the rack translates along its longitudinal axis in proportionto the amount of rotation of the pinion gear, causing medical device4300 to translate with it.

Reference is now made to FIG. 42, which presents a more detailedillustration of means for effecting rotational motion about DOF 4315.Worm gear and drive 4315 a and 4315 b are mated to rack 4316 a asdescribed above. Worm gear 4315 a is rigidly connected to spur gear 4315d. Spur gear 4315 d is mated to a second spur gear 4315 c; in preferredembodiments of the invention, the axes of rotation of gears 4315 d and4315 c are substantially parallel. Spur gear 4315 c is rigidly connectedto, and turns about substantially the same axis as, intermediate gear4315 e. Intermediate gear 4315 e is mated to input gear 4315 f; asillustrated in the figure, input gear 4315 f is disposed such that itmay rotate in a plane different from the plane of rotation ofintermediate gear 4315 e. In preferred embodiments of the invention, therotation axes of gears 4315 e and 4315 f are substantiallyperpendicular. Input gear 4315 f is rigidly connected to one end ofinternal tube 4315 g and rotates about an axis substantially coincidentwith the longitudinal axis of 4315 g. The sequence of steps that leadsto rotational motion about DOF 4315 is thus as follows: rotation ofinternal tube 4315 g drives rotation of input gear 4315 f, which drivessimultaneous rotation of intermediate gear 4315 e and spur gear 4315 c.Rotation of spur gear 4315 c drives rotation of spur gear 4315 d andhence of worm drive 4315 a. Rotation of worm drive 4315 a drivesrotation of worm gear 4315 b, which due to its inability to rotaterelative to rack 4316 a, causes rotation of rack 4316 a and hence ofmedical device 4300 located within. This rotational motion is thusindependent of any other motion of the device or of the connecting meansas a whole.

Reference is now made to FIG. 43B, which illustrates in more detailmeans for effecting translational motion about DOF 4316. Pinion 4315 b(the pinion is not visible in this view) is fixed in place relative tothe gear assembly, but is free to rotated about its principal axis, andis mated to spur gear 4316 c. Spur gear 4316 c is connected by a fixedaxle to a second spur gear 4316 d such that the two gears rotate intandem. The second spur gear 4316 d is mated to intermediate gear 4316e. In preferred embodiments of the invention, the axis of rotation ofintermediate gear 4316 e is substantially parallel to the axleconnecting spur gears 4316 c and 4316 d. In some embodiments of theinvention, intermediate gear 4316 e is rigidly connected to, and turnsin tandem with, a second intermediate gear with a gear ratio other than1:1. Intermediate gear 4316 e (or the second intermediate gear in thoseembodiments that comprise it) is mated to input gear 4316 f. Inpreferred embodiments of the invention, the axis of rotation of inputgear 4316 f is substantially perpendicular to that of intermediate gear4316 e. Input gear 4316 f is rigidly connected to internal tube 4316 gand rotates about an axis substantially coincident with the longitudinalaxis of internal tube 4316 g. Thus, translational motion of medicaldevice 4300 is effected as follows: rotation of internal tube 4316 g andhence of input gear 4316 f drives rotation of intermediate gear 4316 e.Rotation of intermediate gear 4316 e then drives rotation of spur gear4316 d. Since spur gear 4316 c is physically connected to spur gear 4316d, rotation of the latter necessarily causes rotation of the former atthe same angular velocity. Rotation of spur gear 4316 c then drivesrotation of pinion 4316 b, which forces translational motion of rack4316 a and hence of the medical device contained within.

We claim:
 1. A two-part robotic device for positioning of a medicalinstrument, comprising: a. a rigidly mountable fixed base unitattachable to a fixed point in space; and b. a detachable body unitreversibly coupleable to said fixed base unit, coupleable to saidcurrent medical instrument, wherein said fixed base unit is adapted toprovide independent movement to said medical instrument, saidindependent movement selected from a group consisting of rotation andtranslation, and said detachable body unit is removable and replaceablefrom said fixed base unit such that upon exchange of said medicalinstrument for a second medical instrument, said second medicalinstrument is placed in substantially the same location as the locationof said medical instrument prior to said exchange, wherein saiddetachable body comprises k consecutive arm sections, where k is apositive integer, and k−1 joints, an sth joint coupling an sth armsection to an (s+1)st arm section, s being between 1 and k−1, such thatdifferent arm sections of said detachable body are removable andreplaceable, and wherein at least one said joint comprises lockingmeans; said locking means are adapted to lock at least one of said k−1joints in a desired direction; said locking means having at least twostates, a locked state and an unlocked state; wherein, in said lockedstate, either said sth joint and said (s+1)st arm section rotate as aunit about a main longitudinal axis of said sth arm section or said sthjoint and said sth arm section is rotatable as a unit about a mainlongitudinal axis of said (s+1)st arm section; and, in said unlockedstate, the angle between said sth arm section (s+1)st arm section ischangeable.
 2. The two-part robotic device according to claim 1, whereinsaid medical instrument is selected from a group consisting ofendoscope, laparoscope, forceps, and any combination thereof.
 3. Thetwo-part robotic device according to claim 1, wherein said detachablebody unit is an endoscope positioning device comprising means forproviding to said endoscope at least 7 degrees of freedom (DOF) selectedfrom a group consisting of at least 6 rotation movements (1007, 1009,1010, 1011, 1012, 1013, 1601, 1602), at least 1 translation movement(1008) and any combination thereof; further wherein: a. each of said kconsecutive arm sections comprises n coaxial input shafts adapted to berotated around an input axis of rotation by m sources of torque, whereinn, m, and k are positive integers, and further wherein said endoscope iscoupled to one of said k consecutive arm sections; and b. each of saidjoints being a constant velocity coupler comprising: n coaxial inputtransmission means, each of which is coupled to one of said n inputshafts, said input transmission means defining a first planesubstantially perpendicular to said input axis of rotation; n coaxialsecond transmission means rotatably connected to said n inputtransmission means, said second transmission means rotating in a secondplane, said second plane substantially perpendicular to said firstplane; n coaxial output transmission means rotatably connected to said nsecond transmission means, said output transmission means rotating in athird plane; said third plane being substantially perpendicular to saidsecond plane; and n coaxial output shafts, each of which is coupled toone of said n output transmission means, said n output shafts beingadapted to rotate around an output axis of rotation such that (i)turning a given input shaft at a constant velocity will provide aconstant velocity at the corresponding output shaft; and (ii) the anglebetween said input axis of rotation and said output axis of rotationvaries in said second plane in an angular range of about 0 to about 360degrees.
 4. The two-part robotic device according to claim 1, whereinsaid fixed base unit comprises h consecutive arm sections and h−1joints, h being a positive integer, such that different arm sections ofsaid fixed base unit are removable and replaceable.
 5. The two-partrobotic device according to claim 4, wherein: a. each of said hconsecutive arm sections of said fixed base unit comprises q coaxialinput shafts adapted to be rotated around an input axis of rotation by psources of torque, where q, p, and h are positive integers, whereineither said current instrument or said detachable body unit iscoupleable to one of said h consecutive arm sections; b. said fixed baseunit further comprises at least h−1 constant velocity couplers couplingeach pair of said k consecutive arm sections together, each of saidconstant velocity couplers comprising: i. q coaxial input transmissionmeans, each of which is coupled to one of said q input shafts, whereinsaid input transmission means define a first plane substantiallyperpendicular to said input axis of rotation; ii. q coaxial secondtransmission means rotatably connected to said q input transmissionmeans, said second transmission means rotating in a second planesubstantially perpendicular to said first plane; and iii. q coaxialoutput transmission means rotatably connected to said q secondtransmission means, said output transmission means rotating in a thirdplane substantially perpendicular to said second plane; and c. q coaxialoutput shafts, each of which is coupled to one of said q outputtransmission means, said q output shafts adapted to rotate around anoutput axis of rotation; such that (i) turning a given input shaft at aconstant velocity will provide a constant velocity at the correspondingoutput shaft and (ii) the angle between said input axis of rotation andsaid output axis of rotation varies in said second plane in an angularrange of about 0 to about 360 degrees.
 6. The two-part robotic deviceaccording to claim 5, wherein said input transmission means, secondtransmission means, and said output transmission means are selected froma group consisting of gearwheels, wheels, crown gears, bevel gears, spurgears, belts, and any combination thereof.
 7. The two-part roboticdevice according to claim 5, additionally comprising: a. an axialsupport member (601) adapted to provide axial support to said q outputshafts in said third plane; and, b. a circular track (618) centered onthe axis of rotation of said second transmission means, said axialsupport member being adapted to fit into said track and slide within it.8. The two-part robotic device according to claim 5, additionallycomprising a radial support member (604) adapted to provide radialsupport to said q output shafts, said radial support member beingadapted to rotate in said second plane.
 9. The two-part robotic deviceaccording to claim 5, wherein the gear ratio between said input andoutput shafts is between about 10 and about 0.1.
 10. The two-partrobotic device according to claim 5, additionally comprising q coaxialauxiliary shafts in rotating communication with said q secondtransmission means, said q coaxial auxiliary shafts rotating in saidsecond plane, and said q coaxial auxiliary shafts capable of eitherbeing driven by said input shafts or driving said input shafts.
 11. Thetwo-part robotic device according to claim 5, wherein said locking meansis adapted for preventing relative movement between one or more of saidinput axis shafts and said constant velocity joint, wherein saidconstant velocity joint is caused to rotate as a body with said lockedinput axis shafts.
 12. The two-part robotic device according to claim 5,wherein said locking means is adapted for preventing relative movementbetween one or more of said output axis shafts and said constantvelocity joint, wherein said constant velocity joint is caused to rotateas a body with said locked output axis shafts.
 13. The two-part roboticdevice according to claim 3, wherein said input transmission means,second transmission means, and said output transmission means areselected from a group consisting of gearwheels, wheels, crown gears,bevel gears, spur gears, belts, and any combination thereof.
 14. Thetwo-part robotic device according to claim 1, wherein at least one jointis adapted to rotate said current medical instrument about two mutuallyperpendicular axes in the x-y plane.
 15. The two-part robotic deviceaccording to claim 3, additionally comprising: a. an axial supportmember (601) adapted to provide axial support to said n output shafts insaid third plane; and, b. a circular track (618) centered on the axis ofrotation of said second transmission means, said axial support memberbeing adapted to fit into said track and slide within it.
 16. Thetwo-part robotic device according to claim 3, additionally comprising aradial support member (604) adapted to provide radial support to said noutput shafts, said radial support member being adapted to rotate insaid second plane.
 17. The two-part robotic device according to claim 3,wherein the gear ratio between said input and output shafts is betweenabout 10 and about 0.1.
 18. The two-part robotic device according toclaim 3, additionally comprising n coaxial auxiliary shafts in rotatingcommunication with said n second transmission means, said n coaxialauxiliary shafts rotating in said second plane, and said n coaxialauxiliary shafts capable of either being driven by said input shafts ordriving said input shafts.
 19. The two-part robotic device according toclaim 3, additionally comprising a radial support member (604) adaptedto provide radial support to said n output shafts, said radial supportmember being adapted to rotate in said second plane.
 20. The two-partrobotic device according to claim 3, wherein the gear ratio between saidinput and output shafts is between about 10 and about 0.1.
 21. Thetwo-part robotic device according to claim 3, additionally comprising ncoaxial auxiliary shafts in rotating communication with said n secondtransmission means, said n coaxial auxiliary shafts rotating in saidsecond plane, and said n coaxial auxiliary shafts capable of eitherbeing driven by said input shafts or driving said input shafts.